1. Field of the Invention
The invention relates to a detection-alarm mechanism for a tire, and more particularly relates to a detection-alarm mechanism detecting cracks in tires.
2. Description of the Related Art
The tire pressure inspection, such as Tire Pressure Monitoring System (TPMS) is a well established motor vehicle safety standard. A tire wear inspection specification for parked vehicles exists. There is however, no tire wear inspection for vehicles in motion.
Piezoelectric elements, such as piezoelectric fiber, piezoelectric crystal, piezoelectric resistor, or combination of piezoelectric elements and strain gauges are employed as tire deformation sensors installed on the tires of heavy vehicles.
U.S. Pat. No. 7,000,462 discloses a tire pressure and deformation detecting mechanism comprising piezoelectric elements or combination of piezoelectric elements and strain gauges. Pressure and deformation detected by the tire pressure and deformation detecting mechanism are converted into signals transmitted by radio to a host installed in the vehicle.
U.S. Pat. No. 6,910,372 discloses a non-contact monitoring mechanism disposed in the space formed by a tire and a wheel. The non-contact monitoring mechanism comprises a processor and antenna on the middle portion thereof. At least six equal-distanced probes extend from the middle portion.
U.S. Pat. No. 5,749,984 discloses a real-time monitoring mechanism detecting the inclination of a tire with a ratio of the length of an adhesive sheet to the periphery of a tire. An area of a tire surface contacting the ground within a safe range defines reference points. A sensor is disposed in the tire to detect whether the tire is within the safe range. If the tire is within the safe range, the sensor generates a first signal, and otherwise generates a second signal. The sensor also comprises piezoelectric elements.